The agent for Minnesota Vikings tackle DeMarcus Love says his client accidentally took a banned substance that was in a product he purchased at a nutrition store.

The NFL announced Thursday it has suspended Love four games for violating its policy on performance-enhancing drugs.

"DeMarcus Love inadvertently took a banned substance that was in a product he purchased at GNC," Love's agent, Thomas Sims, wrote in an email to USA TODAY Sports.

"DeMarcus takes full responsibility. It was (an) honest (and) unintentional mistake. DeMarcus deeply regrets this unfortunately situation. He looks forward to resuming his playing career with the Vikings organization and contributing to the 2013 football season."

Love, 25, will be eligible to return the active roster on Sept. 30, though his chances for making the team always appeared slim.

A sixth-round draft pick out of Arkansas in 2011, he was inactive for every game as a rookie and spent last season on injured reserve after undergoing surgery for a torn pectoral muscle.

Love is eligible to participate in all practices and preseason games before his suspension begins.